One of the problems with writing ideological, controversial, or religious material, such as everything on LewRockwell.com, is this: the marginal cost of sending e-mail is zero, except for the time involved. A published writer with a strong opinion, such as everyone who writes for LewRockwell.com, is going to get e-mail from people who want to express another opinion.

Most of these letters are civil. Some are hostile. A few are incoherent. But some are of the “you did not prove your case” variety. These are the dangerous ones.

If you respond, you are taking a big risk. The letter-writer almost certainly has never published anything. If he has published something, no one has read it. He wants a response from you because no one has ever paid much attention to him. And e-mail is free.

If you ignore the letter, you have become the latest in the person’s long line of people who have ignored him. He really does not expect you to respond. But if you do respond, you have just punched your fist into a tar baby. You have acknowledged his existence. Now, he expects you to refute him. No, he demands that you refute him. Can you refute him to his satisfaction? It would have been easier for the Pope to have persuaded Luther that he had it all wrong.

The problem with tar babies is that their time is of no value to them. They think that your time is of no value to you. And e-mail is free.

“You haven’t answered my argument!” The tar baby expects an answer, once you have responded. But what the payoff if you persuade him that he is wrong is never said. You will get credit for . . . what?

He is like the kid with the new Colt revolver in the old West. He can make a name for himself if he shoots the old gunfighter. “I’m calling you out, Ringo!” The trouble with tar babies is that the bullets are blanks. “You missed me, Ringo! You weren’t fast enough.” This can go on — will surely go on — indefinitely.

There is real skill in deciding who is worth a response and who isn’t. F. A. Hayek refused to respond to Keynes’s General Theory (1936) because he had spent so much time in exchanges with Keynes after his critical, 26-page review of Keynes’s Treatise on Money (1930), which appeared in Economica in 1931. Keynes published a heated reply, and then Hayek replied. They exchanged 12 private letters over four months, 1931-32.

Hayek offered several explanations over the years for his failure to respond to the General Theory. One was that he figured Keynes would change his mind again. Another was that he thought the book was a tract for the times. Another was that he was tired of controversy. There were others. These are listed in an essay by Bruce Caldwell. Whatever the reason, Hayek later regretted it.

Keynes was a classic tar baby, but he was not a wanna-be. He was the Goliath who had laid down the challenge. He called out all comers. Hayek played the role of King Saul, but David never showed up. Well, he did, in 1959. Henry Hazlitt wrote the readable and masterful book, The Failure of the ‘New Economics’, but the academic world ignored it. Hazlitt was not a college graduate, he wrote in English, and he was 23 years too late. The Philistines won the war for the biblical forty years.

Then what of the wanna-be Goliaths with their free e-mail? My advice — not always followed — is to let them bellow their challenges. No one can hear them anyway.

The “Delete” key is just as large as the “Reply” key.

Use it.